Method SetCurrentRenderer

Rendering/Core/vtkInteractorObserver.cxx:62–104

------------------------------------------------------------------------------

//------------------------------------------------------------------------------
void vtkInteractorObserver::SetCurrentRenderer(vtkRenderer* _arg)
{
  if (this->CurrentRenderer == _arg)
  {
    return;
  }

  if (this->CurrentRenderer != nullptr)
  {
    this->CurrentRenderer->UnRegister(this);
  }

  // WARNING: see .h, if the DefaultRenderer is set, whatever the value
  // of _arg (except nullptr), we are going to use DefaultRenderer
  // Normally when the widget is activated (SetEnabled(1) or when
  // keypress activation takes place), the renderer over which the mouse
  // pointer is positioned is used to call SetCurrentRenderer().
  // Alternatively, we may want to specify a user-defined renderer to bind the
  // interactor to when the interactor observer is activated.
  // The problem is that in many 3D widgets, when SetEnabled(0) is called,
  // the CurrentRender is set to nullptr. In that case, the next time
  // SetEnabled(1) is called, the widget will try to set CurrentRenderer
  // to the renderer over which the mouse pointer is positioned, and we
  // will use our user-defined renderer. To solve that, we introduced the
  // DefaultRenderer ivar, which will be used to force the value of
  // CurrentRenderer each time SetCurrentRenderer is called (i.e., no matter
  // if SetCurrentRenderer is called with the renderer that was poked at
  // the mouse coords, the DefaultRenderer will be used).

  if (_arg && this->DefaultRenderer)
  {
    _arg = this->DefaultRenderer;
  }

  this->CurrentRenderer = _arg;

  if (this->CurrentRenderer != nullptr)
  {
    this->CurrentRenderer->Register(this);
  }

  this->Modified();
}

//------------------------------------------------------------------------------
// This adds the keypress event observer and the delete event observer